* {
    margin: 0;
    padding: 0;
 text-decoration: none;
}
a{
    color: #444;
}

.preview {
    width: 998px;
    height: 200px;
    margin: 30px auto;
    img {
        width: 100%;
        height: 100%;

    }
}
.dt-cat{width: 998px;
    height: 300px;
    border: 1px solid #e0e0e0;
    background-color: #fff;
    margin: 0 auto;
   
   h2{
    width: 100%;
    height: 30px;
    margin-bottom: 18px;
    line-height: 30px;
    text-align: center;
    font-size: 22px;
    font-weight: 700; 
    color: #444;
  } 

}

.threeall{
    margin: 20px auto;
    width: 90%;
    height: 200px;
  
    .three{
          
            width: 33%;
            height: 100%;
            float: left;
            border-right: 1px solid #666;
        }

}
.dt-cat-nav{

width: 118px;
    height: 40px;
    background-color: orange;
    margin-left: 131px;
  span{
    color: #777;
    line-height: 20px;
    font-size: 14px;    
    display: block;
    height: 20px;
     padding-top: 10px;
    }
    i{
        font-size: 18px;
        margin-left: 46px;
        margin-top: -18px;
        position: absolute;
    }
    a{
        display: block;
        width: 36px;
        height: 21px;
        text-decoration: none;
        position: absolute;
        margin-left: 69px;
        margin-top: -20px;
        font-size: 14px;    
         color: #777;



    }
}
.box{
   
    
    position: relative;
    margin: 0 auto;
    width: 1000px;
}
.item{
    position: absolute;
    img{
        width: 100%;
        height:100%;
    }
}


